Get scraper metrics (Prometheus integration)

Problem

You want to get scraper metrics for your Prometheus OpenMetrics integration with New Relic for Docker or Kubernetes.

Docker: If you configure the http://localhost:8080/metrics endpoint, the integration will also scrape its own metrics.

Kubernetes: By default, the scraper will also scrape its own metrics.

To learn more about what is happening inside the scraper, use the following metrics for your Docker or Kubernetes integration with New Relic:

Metric	Description
`nr_stats_targets`	Discovered targets by retriever (for example, Fixed, Kubernetes).
`nr_stats_fetch_errors_total`	Fetches attempted that resulted in an error by target.
`nr_stats_discoveries_total`	Attempted discoveries by retriever (for example, Fixed, Kubernetes).
`nr_stats_fetches_total`	Fetches attempted by target.
`nr_stats_integration_fetch_target_duration_seconds`	The total time in seconds to fetch the metrics of a target.
`nr_stats_integration_list_targets_duration_by_kind`	The total time in seconds to get the list of targets by resource kind and retriever (for example, Kubernetes Pods, services, etc).
`nr_stats_integration_payload_size`	Size of target's payload.
`nr_stats_integration_process_duration_seconds`	The total time in seconds to process all the steps of the integration.
`nr_stats_integration_total_executions`	The number of times the integration has been executed.
`nr_stats_integration_total_payload_size`	Total size of the payloads scraped.
`nr_stats_metrics_total_timeseries`	The total number of scraped time series.
`nr_stats_metrics_total_timeseries_by_target`	Total number of time series by target.
`nr_stats_metrics_total_timeseries_by_target_type`	Total number of metrics scraped by type and target.
`nr_stats_metrics_total_timeseries_by_type`	Total number of metrics scraped by type.
`nr_stats_discovery_errors_total`	Attempted discoveries that resulted in an error by retriever.